SSSI Efficacy With iACB and PC-LIA in TKA Pain Management

Taipei Medical University

Status: Not yet enrolling

Conditions: Peripheral Nerve Blocks; Postoperative Pain Management in Total Knee Arthroplasty

Treatments: Procedure: posterior capsule local infiltration analgesia (PC-LIA); Procedure: intermittent adductor canal block (iACB); Procedure: Supra-Sartorial Subcutaneous Infiltration (SSSI)

Study type: Interventional

Funder types: Other

Identifiers

NCT07191964

N202503094

Details and patient eligibility

About

This prospective, triple-blinded, sham-controlled randomized trial evaluates the additive effect of Supra-Sartorial Subcutaneous Infiltration (SSSI) combined with intermittent adductor canal block (iACB) and posterior capsule local infiltration analgesia (PC-LIA) for pain management in total knee arthroplasty (TKA). SSSI, a simpler alternative to targeted anterior femoral cutaneous nerve (AFCN) block, is tested in 90 adults (45-90 years) randomized into two arms: sham SSSI + active iACB + PC-LIA versus all active interventions. Primary outcome is pain scores on postoperative day 0; secondary outcomes include daily pain trajectory, opioid use, functional recovery, and complications over days 0-3.

Full description

This prospective, two-armed, triple-blinded, sham-controlled randomized controlled trial investigates the additive effect of Supra-Sartorial Subcutaneous Infiltration (SSSI) to intermittent adductor canal block (iACB) and posterior capsule local infiltration analgesia (PC-LIA) in multimodal pain management for total knee arthroplasty (TKA). SSSI is a peripheral nerve block technique the investigators devised as a simpler alternative to targeted anterior femoral cutaneous nerve (AFCN) block, which is technically more demanding and time-consuming. Based on the investigators' preliminary study (in publication) where SSSI combined with PC-LIA provided clinically meaningful analgesia in ~58% of patients, and drawing from previous studies on AFCN blocks, the trial compares: Arm 1 (all active SSSI + active iACB + active PC-LIA) versus Arm 2 (sham SSSI + active iACB + active PC-LIA). Adults (45-90 years) undergoing unilateral primary TKA (n=90, 45/arm) will be randomized 1:1, stratified by age, preoperative pain levels (in Numerical Rating Scale) and functional status (WOMAC Index or Knee Society Score). Interventions use 0.3% ropivacaine or saline shams, with SSSI and ACB catheterization performed in the post-anesthesia care unit by anesthesiologists and PC-LIA performed intraoperatively by surgeons. Primary outcome: Numerical Rating Scale pain scores at rest and during continuous passive motion at 9:00 PM on postoperative day (POD) 0, focusing on anteromedial knee pain. Secondary outcomes include daily pain scores, rescue ACB doses, additional opioid use, functional recovery (quadriceps strength, timed up and go [TUG] test), and complications over POD 0-3. With ~96% power for a 2-point NRS difference, this trial evaluates SSSI's role in enhancing motor-sparing analgesia.

Enrollment: 90 estimated patients

Sex: All

Ages: 45 to 90 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Adults aged 45-90 undergoing unilateral primary TKA for osteoarthritis.
• American Society of Anesthesiologists (ASA) physical status I-III.
• Able to provide informed consent and use NRS pain scales.
• Surgery scheduled to start before noon to standardize spinal anesthesia recovery.

Exclusion criteria

• Bilateral or revision TKA.
• Contraindications to regional anesthesia (e.g., coagulopathy, infection at injection site).
• Chronic opioid use (>30 mg morphine equivalents/day) or preoperative NRS >4.
• Pre-existing neurological deficits in lower extremities or AFCN-related neuropathy.
• Allergy to ropivacaine.
• Pregnancy, breastfeeding, or cognitive impairment affecting assessments.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Triple Blind

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90 participants in 2 patient groups, including a placebo group

SSSI + iACB + PC-LIA (all active)

Active Comparator group

Treatment:

Procedure: Supra-Sartorial Subcutaneous Infiltration (SSSI)

Procedure: intermittent adductor canal block (iACB)

Procedure: posterior capsule local infiltration analgesia (PC-LIA)

SSSI (sham) + iACB + PC-LIA

Placebo Comparator group

Treatment:

Procedure: Supra-Sartorial Subcutaneous Infiltration (SSSI)

Procedure: intermittent adductor canal block (iACB)

Procedure: posterior capsule local infiltration analgesia (PC-LIA)